Jib sheeting angles on a Beneteau 311

[CapitalistSailor]

I have a Beneteau 311, Footloose, and I have been working on getting better tacking angles when going to windward. I measured the jib sheeting angle last night and it works out to almost 15 degrees. For a cruiser that aspires to good performance I would have expected something like 7-10 degrees. The angle I'm referring to is how far out to the side the jib lead is from the centerline of the boat. See for example this article and the second diagram: http://www.sailmagazine.com/racing/regattas/headsail-sheeting/

I have two questions:

1. Do you agree that this sheeting angle seems high?
2. Would using an inhauler (Barber hauler) help me to get a little better angle? The track is about as inboard as it can be without being mounted on the cabin. Or would using an inhauler just make me pinch too much and slow down?

The Neil Pryde tuning guide for the OEM sails suggests that the sheet should be pulled in until the leach is no more than 1/4 of the way in from the outside end of the spreader (1/4 of the length of the spreader). This amount of tightening adds a few more degrees of lead angle.

Thanks in advance for your thoughts.

 

[blat182]

I have read in several articles about sheeting angles being to high on similar size Beneteaus and various methods to reduce the sheeting angle to improve performance. In particular I read on a UK first 31.7 website, who are keen racers, of the improvements they achieve by doing this. I have a first 33.7 with tracks on the coachroof which I use as much as possible for this reason and it definitely improves my windward performance.i couldn't give you specifics but I would recommend you try it yourself and see if it gives you an improvement. Good luck. Ian

 

[DougM]

As a general rule, the jib cars need to be forward on the track in light air, and aft in heavier air. The angle of the sheet lead should appear to be nearly perpendicular to the forestay. One issue to consider if you barber haul the sail is that you may be limited by the sail contacting the tip of the spreader. If the shrouds are inboard of the tracks.

 

[CapitalistSailor]

One issue to consider if you barber haul the sail is that you may be limited by the sail contacting the tip of the spreader. If the shrouds are inboard of the tracks.

Doug,

On the Beneteau 311, the lead and track for the standard 116% jib is inside of the spreaders, which limits the size of the jib that can be carried. The leach of the sail is about 1-2" in front of the spreaders when the sail is sheeted in for close-hauled. If I had a larger jib, such as a 155% jib. it would have to be sheeted outside of the spreaders and maybe another 5' back.

 

[CapitalistSailor]

Are there any more comments from the forum? I am looking for advice on whether an inhauler or barber hauler would help me improve my tacking angles on my Beneteau 311, or would just cause me to pinch too much. I am asking about the side to side placement of the jib clew, not the fore and aft placement. The existing track gives me a sheeting angle of about 15 degrees.

 

[Jackdaw]

Ah yes. For good reason, non-overlapping rigs have left the sole domain of hard-core race boats and trickled into cruising platforms. With the exception of light air reaching, a fractional boat with a big(ish) mainsail and a non-overlapping jib makes for a very effective sailplan.

The big challenge is where to put the jib track. As noted the proper sheeting angle for mortal boats is around 9 degrees. The problem is this often is the exact spot the cabin trunk wall is, and/or cabin windows.

Like on the 311. As a solution Beneteau goes low, widens the sheeting angle into the mid-teens. Probably OK for most people on a cruiser.

On our First 260 Finot goes on top for the track, the boat design optimized for this, and gets the sweet sheeting angle of 9 degrees along the entire track.

Along with the overall boat design, this allows for amazing windward performance. In 14 knots of breeze our True Wind Angle (TWA) at best windward VMG is a very tight 37.6 degrees. The apparent wind angle is 27 degrees. It feels like we are sailing straight into the wind.

So what to do if your angle is wide? Remember that pointing is a function of overall boat design, so you might not hit 38 TWA, but there are things you can do. Inhaulers for sure will help in the right conditions. These are quite common, and actually standard on the First 35. Like your boat, it has tracks below the windows and and needs to in-hauled for optimal windward performance.

The system looks like this.

The jib sheet is held captive after the car by a low-friction ring attached to the deck inboard of the track by a 2:1 dyneema purchase. This line leads back to the cockpit where is is adjusted. On some inhauler systems there is a control line for each side. More complex setups allow one control line to drive the rings on both sides. This makes for easier tack-to-tack setup.

Going upwind with very tight sheeting angle takes full-time concentration. Often your first indication of pinching is the entire luff collapsing. But the rewards are there!

Boats with the tight angle setup have their own issues to deal with... when jib reaching we use OUTHAULERS to pull the clew outward and keep the entire sail in gear.

It never ends. If you are looking to really optimize your up-wind performance, I'd suggest adding remotely adjustable jib car controls to your tracks. Tweaking a high-aspect jib like this requires your cars to be adjusted as much as the sheet tension. Its one of the best mods you can make to a non-overlapper.

 

[bob_pattison]

sheeting angles

Doug,
The jib as designed is at a 15degree sheeting angle...as this is where the tracks are.
Our jib sheets inboard as pointed out in a few of the posts here...so when sheeted in tight it will be well inboard of the spreader tip and about 1/2 to 1/4 from the spreader (where the leech meets the spreader).

Barberhauling inboard is a good way to power up the sailplan in light air and help with pointing. Lot's of boats and classes do it..the J-109 class as an example.
The key is to just try it out and see how the boat performs...in a variety of wind strengths.
You should quickly find out if the boat is faster /higher and at what wind strength the gains start to flatten out.

Bob Pattison
NP Sails

I have a Beneteau 311, Footloose, and I have been working on getting better tacking angles when going to windward. I measured the jib sheeting angle last night and it works out to almost 15 degrees. For a cruiser that aspires to good performance I would have expected something like 7-10 degrees. The angle I'm referring to is how far out to the side the jib lead is from the centerline of the boat. See for example this article and the second diagram: http://www.sailmagazine.com/racing/regattas/headsail-sheeting/

I have two questions:

1. Do you agree that this sheeting angle seems high?
2. Would using an inhauler (Barber hauler) help me to get a little better angle? The track is about as inboard as it can be without being mounted on the cabin. Or would using an inhauler just make me pinch too much and slow down?

The Neil Pryde tuning guide for the OEM sails suggests that the sheet should be pulled in until the leach is no more than 1/4 of the way in from the outside end of the spreader (1/4 of the length of the spreader). This amount of tightening adds a few more degrees of lead angle.

Thanks in advance for your thoughts.

 

[CapitalistSailor]

Ah yes. For good reason, non-overlapping rigs have left the sole domain of hard-core race boats and trickled into cruising platforms. With the exception of light air reaching, a fractional boat with a big(ish) mainsail and a non-overlapping jib makes for a very effective sailplan........

Like on the 311. As a solution Beneteau goes low, widens the sheeting angle into the mid-teens. Probably OK for most people on a cruiser.

...... Inhaulers for sure will help. These are quite common, and actually standard on the First 35. Like your boat, it has tracks below the windows and and needs to in-hauled for optimal windward performance.

The jib sheet is held captive after the car by a low-friction ring attached to the deck inboard of the track by a 2:1 dyneema purchase. This line leads back to the cockpit where is is adjusted. On some inhauler systems there is a control line for each side. More complex setups allow one control line to drive the rings on both sides. This makes for easier tack-to-tack setup.

Going upwind with very tight sheeting angle takes full-time concentration. Often your first indication of pinching is the entire luff collapsing. But the rewards are there!

Jackdaw,

I appreciate the thorough response, and the pictures. The low-friction ring looks like something I could rig up to try without too much fuss. I already move the lead to the rail when reaching (or partly, for close reaching, using two lead locations and two sheets together). I also move the jib lead forward and back depending on wind strength and how the sail looks on any given day, but the car is adjusted with a pin, rather than a continuously variable block and tackle.

 

[CapitalistSailor]

Re: sheeting angles

Bob,

Thank you for your response. I will give it a try and see how my VMG works out. Or better yet, I'll just chase another boat that points pretty well and see how my angles and speed compare.

For most of this summer, it's been blowing really hard, or the wind has been 4 kn or less, so objective data has been hard to collect. Some of the big races on the western end of Lake Erie were cancelled beforehand or en route. I seem to be doing OK compared to the polars (for a B323), except for close-hauled.

I race on other people's boats that are used strictly for racing, so I should have a feel for what's good performance.

I've borrowed an asymmetrical spinnaker and some spinnaker sheets, and bought some blocks, so I'll give that a try soon also to see what will work and where things need to be located.

I do most of my sailing on my boat single- or doublehanded, so I keep that in mind when trying to decide how to set things up.

 

[Jackdaw]

Jackdaw,

I appreciate the thorough response, and the pictures. The low-friction ring looks like something I could rig up to try without too much fuss. I already move the lead to the rail when reaching (or partly, for close reaching, using two lead locations and two sheets together). I also move the jib lead forward and back depending on wind strength and how the sail looks on any given day, but the car is adjusted with a pin, rather than a continuously variable block and tackle.

I get all that!

Some thoughts:

All the value in a polar chart is in the data in the MAX upwind and downwind VMG columns. Everything else is just reaching, and all boats do that well.

A designer will often match the rig sheeting angle with the rest of the boat's expected performance. Things like righting moment, keel configuration, waterform etc will also effect pointing and potentially lower the 'bang for the buck' in tightening sheeting angle.

Lastly, remember that because of the last point, tightening the sheeting angle may make the boat appear to point better, but ending up giving most of the real gain back in slideslip. In particular with a shoal, less effective keels. When testing,we always have two compasses, one on heading and one on course so we can measure sideslip. At polar upwind, our 36.7 (7.5 foot draft) slip ranges from 2 to 7 degrees. Some boats slip will over 10!

 

[CapitalistSailor]

I get all that!

Some thoughts:

Lastly, remember that because of the last point, tightening the sheeting angle may make the boat appear to point better, but ending up giving most of the real gain back in slideslip. In particular with a shoal, less effective keels. When testing,we always have two compasses, one on heading and one on course so we can measure sideslip. At polar upwind, our 36.7 (7.5 foot draft) slip ranges from 2 to 7 degrees. Some boats slip will over 10!

Jackdaw,

You make a good point about the leeway going to windward. I have been using the GPS plot to gauge my tacking angles. I should start comparing that to what I see on the compass. I'm used to 5 degrees on many types of (sail)boats, but it could easily be 10 if I'm not moving fast enough.

 

[Jackdaw]

Jackdaw,

You make a good point about the leeway going to windward. I have been using the GPS plot to gauge my tacking angles. I should start comparing that to what I see on the compass. I'm used to 5 degrees on many types of (sail)boats, but it could easily be 10 if I'm not moving fast enough.

For sure. Your tacking angle will appear to be 10 degrees wider (at least!) on your GPS vs a mag compass.

 

[CapitalistSailor]

For sure. Your tacking angle will appear to be 10 degrees wider (at least!) on your GPS vs a mag compass.

I assume the polar charts are using the compass angles, and therefore do not include the affect of leeway, but I never thought about that before?

 

[Jackdaw]

I assume the polar charts are using the compass angles, and therefore do not include the affect of leeway, but I never thought about that before?

Correct.

Most good polar charts will also indicate both heel angle and sideslip. We monitor both like a hawk, in particular when it's breezy.